Apparatus for closing filled bags



May 28, 1963 T. LANZ 3,091,198

APPARATUS FOR CLOSING FILLED BAGS Filed Dec. 15 1960 S Sheets-Sheet 1 FIG. 2.

FIGI.

May 28, 1963 e. T. LANZ APPARATUS FOR CLOSING FILLED BAGS 3 Sheets-Sheet 2 Filed Dec. 15, 1960 FIGB.

FIGS.

y 23, 1963 G. T. LANZ 3,091,198

APPARATUS FOR CLOSING FILLED BAGS Filed Dec. 15, 1960 3 Sheets-Sheet 5 FIG .4

v ,4/ J3; O I 1L fillllliul I W Q 32 6% H I i m I I2 I 1 I I 21 17 Uite rates Patent fifice iifi hl Patented May 28, 1963 3,691,198 APPARATUS FQR CLOSING FHILED BAGS George T. Lana, Kirirwood, Mm, assignor to Ralston Purina Company, St. Louis, Mo., a corporation of Missouri Filed Dec. 13, 1960, Ser. No. 75,610 8 Claims. (Cl. 112-11) This invention relates to apparatus for closing filled bags of the type including a sewing machine for sewing the tops of filled bags, and more particularly to a roller attachment for such apparatus for supporting the top of each bag as it exits from the sewing machine.

Among the several objects of the invention may be noted the provision of an attachment of the class described which facilitates the severance of the sewing thread chain extending between the sewing machine and the trailing end of the bag top; the provision of such an attachment which will accommodate bag tops of difierent thicknesses; the provision of such an attachment which may be easily rendered inoperable, thereby making it possible to sew bags which may not need the top support supplied by the attachment; the provision of such an attachment which reduces the labor required of the ma chine operator; and the provision of such an attachment which is both simplified and economical in construction and reliable in operation. Other objects and features wil be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a plan view of a sewing apparatus including an attachment of this invention, showing a sewn bag on the exit side shortly after the sewing thread chain has been cut;

FIG. 2 is a plan view similar to FIG. 1 showing the sewing thread chain cutting operation;

FIG. 3 is an enlarged vertical section taken on line 33 of FIG. 1;

FIG. 4 is an enlarged vertical section taken on line 44 of FIG. 1;

FIG. 5 is an enlarged vertical section taken on line 55 of FIG. 2, with certain parts removed;

FIG. 6 is a side elevation showing certain roller gears, and illustrating one of the roller gears locked out of mesh with the other gear; and

FIG. 7 is a vertical section taken on line 7-7 of FIG. 4, with certain parts removed.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

With certain prior apparatus for sewing closed the tops of filled bags, and particularly as regards textile bags, the operator of the apparatus has had to guide the top of a filled open-mouth bag into the sewing machine on the entry side, then step around to the exit side as the bag top is traveling through the machine and push the sewing thread chain extending between the sewing machine and the trailing end of the bag toward a cutter. Recently, on some machines, an air-operated pusher has been provided for pushing the sewing thread chain into the cutter. However, while such a pusher accomplishes its intended function with respect to paper bags which, due to the inherent rigidity of the paper, nonmally hold the sewing thread chain in a generally horizontal line so that it will be aligned with the pusher as the pusher pushes the sewing thread chain toward the cutter, textile bags are not as rigid as paper bags and the tops of the bags tend to fall over as the bag exits from the sewing machine, thereby tending to pull the thread chain out of alignment with the pusher. Consequently, when textile bags are sewn on such equipment, the operator is required to step around to the exit side of the sewing machine and hold the bag top up to keep the sewing thread chain in alignment with the pusher. By the use of the roller attachment of this invention, textile bag tops are automatically held up, and a considerable amount of labor on the part of the operator is eliminated.

Now referring to FIGS. 1 and 2 of the drawings, there is shown an apparatus for closing filled bags which, apart from the provision of a roller attachment of this invention, may be of a commercially available type. As shown, the apparatus includes a conveyor 1 adapted to convey filled bags B in upright position one after another through a sewing station. A sewing machine 3 is mounted in fixed position at this station for horizontal operation of its needle N to stitch the top of the bags. The sewing machine has the usual feed dog 5 for feeding the top of the bags therethrough and the usual presser foot 7. A cutter 9 is provided for cutting the chain C of thread trailing a sewn bag after the trailing end of the bag top exits from the sewing machine. Cutter 9 is a vertically reciprocating cutter being continuously driven by mechanism in the sewing machine when the latter is in operation. It is offset from the line of stitching as appears in FIGS. 1 and 2, and consequently means is provided for moving the sewing thread chain C into position for being cut by the cutter as the top of each bag exits from the sewing machine. This means comprises an air cylinder 11 mounted in horizontal position on the exit side of the sewing machine at the level of the needle N. Push rod 13 extends from piston 15 in the cylinder 11 in the direction toward the line of stitching, and has a fork 17 at its end adapted to catch the sewing thread chain when the piston 15 is moved forward and deflect the chain C into the path of the cutter 9 (see FIG. 2), whereupon the chain is severed by the cutter (which is continuously reciprocating when the sewing machine is in operation). Suitable means (not shown) is provided for supplying air to the cylinder for operating the piston and push rod when the trailing end of a bag top passes the fork 17. Such apparatus is conventional and well known in the art, being of a type such as is manufactured and sold by Union Special Machine Company of Chicago, Illinois.

When paper bags are fed through and being sewn by the apparatus, the inherent rigidity of the paper will normally hold the paper bag top up and the sewing thread chain in general horizontal alignment with the fork 17 on the push rod 13 so that upon operation of the rod, the fork will catch the sewing thread chain C and move toward the cutter Q. However, when textile bags are being fed through and sewn by the machine the tops of the bags and the sewing thread chain extending therefrom will tend to fall over as the bag top exits from the machine. This is due to the fact that textile bags do not have the inherent rigidity necessary to maintain the tops thereof in an upright fashion. As a result, the fork 17 will often miss the sewing thread chain unless the machine operator holds up the top of the bag and/ or keeps the sewing machine thread between the bag and the needle in a taut condition. In accordance with this invention, a roller attachment A is provided which positively holds up the tops of textile bags and maintains the thread chain taut for proper operation, eliminating any necessity for the machine operator to hold up the top of the bag or otherwise keep the chain taut.

Roller attachment A comprises a pair of rolls 19 and 21 mounted on the exit side of the sewing machine 3 outward of the push rod 13 in position for gripping the tops of bags exiting from the sewing machine in the stitched zone of the bags. These rolls are rotatable on 3 generally vertical axes located on opposite sides of the stitching line and with their pass plane (which is generally vertical) generally in the same plane as the vertical plane of the stitching line. The rolls are relatively movable toward and away from one another, and are biased toward one another for gripping the bag tops. Means is provided for continuously driving the rolls in forward direction at a speed greater than the speed at which the bag tops are fed through the sewing machine by the feed dog 5 of the sewing machine.

More particularly, roll 19 is fixed on the lower end of a vertical shaft 23 journalled in a vertical tubular bearing 25. The latter has laterally extending ears 27 by means of which it is secured as indicated at 29 to a bracket 31 mounted on the sewing machine. Roll 21 is fixed on the lower end of a shaft 33 journalled in a tubular bearing 35 which carries a bag top guide 32. The rolls 19 and 21 are preferably soft rubber rolls. They may be serrated or smooth. As shown, they are helically grooved, but this is not essential. Spur gears 37 and 39 are fixed on the upper ends of shafts 23 and 33, respectively, above the tubular bearings 25 and 35. Bearing 35 is mounted for pivotal movement about a horizontal axis at 41 above the gears and approximately in the pass plane of the rolls. For this purpose, a curved arm 43 extends from hearing 35 around over the gear 39 and has a pivot pin at 45, its upper end. This pin is pivotally mounted in bearings 47 and 49 on an angle bar bracket 51 extending outward from the sewing machine. The pin 45 has an extension 53. A coil spring 55 surrounding this extension and having one end secured to a head 57 at the end of the extension and its other end secured to hearing 47 exerts a bias on the pin tending to turn it counterclockwise as viewed in FIGS. 4 and 6. Accordingly, roll 21 is biased toward engagement with roll 19, and gear 39 is biased into meshing engagement with gear 37. The arrangement is such as to allow for variations in thickness of bag tops. The gears are so formed as to allow for angling of gear 39 relative to gear 37 to some extent without interrupting the driving relationship of the gears as roll 21 moves away from roll 19 on passage of a relatively thick bag top. Additionally, the pivotal mounting of bearing 35 is such as to permit it to be swung away from bearing 25 far enough for disengagement of the gears and relatively wide separation of the rolls (see FIG. 6).

Shaft 23 at its upper end is coupled to the output shaft of a right-angle worm gear drive 59 by means of a universal coupling 61. A flexible drive shaft 63 driven from a suitable power source (not shown) is connected to the input shaft of the worm gear drive. The power source here may be the sewing machine motor or a separate motor. Shaft 23 and roll 19 are thereby continuously driven while the sewingmachine is in operation and the vdrive therefor is such that the peripheral speed of roll 19 is greater (50% greater, for example) than the speed at which the bag tops are fed through the sewing machine by the feed dog 5. With gear 37 in mesh with gear 39, roll 21 is also continuously driven at a speed corresponding that of roll 19.

For holding roll 21 separated from roll 19 and for holding gear 39 out of mesh with gear 37, a latch 65 is pivoted at. 67 on the sewing machine and may be swung from the retracted solid line position shown in FIG. 3 to the dotted line position shown therein for holding bearing 35 in the angled position in which it appears in FIG. 6.

Operation is as follows:

The machine operator holds up the top of a filled textile bag conveyed by conveyor 1 and enters it between the presser foot 7 and the feed dog 5. The top of the bag is then fed through the sewing machine and sewn closed. As the leading portion of the bag top exits from the sewing machine, it is caught in the nip of rolls 19 and 21 before it tends to collapse. Since these rolls are rotating in forward direction at a speed higher than the speed at which the bag top is being fed forward by the sewing machine, they tend to pull the bag top out of the sewing machine and keep it in a taut condition. If the rollers are helically serrated, as shown, the bag tops will also be lifted upward. After the bag top exits from the sewing machine, its trailing end is held in an upright position by the rolls 19 and 21 and the sewing thread chain C extending back from the bag top to the needle N is held taut in horizontal position by the action of rolls 19 and 21. As the trailing end of the bag top passes through the rolls, cylinder 11 is operated to drive push rod 13 forward and deflect the sewing thread chain into the path of cutter 9. As this occurs the machine operator can be starting another bag into the sewing machine.

\Vhen sewing paper bags, the tops of which do not ordinarily need the support that textile bags require, the pivotal roll assembly 21, 33, 35 etc. may be swung away from the other roll assembly 19, 25 etc. and held in retracted position by latch 65. It will be seen that the sewing machine speed and the conveyor speed may be synchronous whether paper or textile bags are being sewn. While it is contemplated that the attachment of this invention will be primarily used for sewing textile bags, it is to be understood that the attachment could be used with all types of bags, including paper bags, if so desired.

Accordingly, it will be observed that the roller attachment A of this invention makes it possible reliably to sever the sewing thread chain C extending back from a sewn bag to the needle, without any necessity for the machine operator stepping around to the exit side of the sewing machine and hold the bag top up to insure severance, and thereby increases the output that can be accomplished by one man and one machine. Further, the attachment is readily adapted for sewing either paper bags or textile bags, without requiring extensive alterations.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above construotions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In an apparatus for closing open-mouthed filled bags, said apparatus comprising a conveyor adapted to convey filled bags in upright position one after another through a sewing station, a sewing machine mounted in fixed position at said station for horizontal operation of its needle to stitch the tops of the bags, said sewing machine having means for feeding the tops of the bags therethrough, a sewing thread cutter for cutting the chain of thread trailing a sewn bag after the trailing end of the bag top exits from the sewing machine, said cutter being offset from the line of stitching, and means for moving the chain into position for being cut by the cutter; means for supporting the top of each bag as it exits from the sewing machine and for holding taut the chain of thread between the sewing machine and the trailing end of the bag top to maintain said chain in position for engagement by said means for moving the chain into position for being cut by the cutter, said bag top supporting means comprising a pair of rolls mounted on the exit side of the sewing machine in position for gripping the tops of bags exiting from the sewing machine in the stitched zone of the bags, said rolls being rotatable on generally vertical axes and being relatively movable toward and away from one another, means biasing said rolls toward one another for gripping bag tops, and means for continuously driving said rolls at a speed greater than the speed at which the bag tops are fed through the sewing machine by said bag top feeding means. 7

2. In apparatus as set forth in claim 1, one of said rolls being mounted for rotation on a fixed generally vertical axis, andthe other of said rolls being mounted'for swinging movement of its axis on a horizontal pivot above the rolls.

3. In apparatus as set forth in claim 2, said other roll being swingable away from said one roll to a n'ongripping position, and means for retaining said other roll in nongripping position.

4. In apparatus as set forth in claim 1, each of said rolls being a resilient roll having helical grooves in its periphery whereby said rolls are adapted to exert a lift on a bag top gripped therebetween.

5. In an apparatus for closing open-mouthed filled bags, said apparatus comprising a conveyor adapted to convey filled bags in upright position one after another through a sewing station, -a sewing machine mounted in fixed position at said station for horizontal operation of its needle to stitch the tops of the bags, said sewing machine having means for feeding the tops of the bags therethrough, a sewing thread cutter for cutting the chain of thread trailing a sewn bag after the trailing end of the bag top exits from the sewing machine, said cutter being offset from the line of stitching, and means for moving the chain into position for being cut by the cutter; means for supporting the top of each bag as it exits from the sewing machine and for holding taut the chain of thread between the sewing machine and the tnailing end of the bag top to maintain said chain in position for engagement by said means for moving the chain into position for being cut by the cutter, said bag top supporting means comprising a pair of rolls mounted on the exit side of the sewing machine in position for gripping the tops of bags exiting from the sewing machine in the stitched zone of the bags, one of said rolls being mounted on the lower end of a first shaft journalled in a generally vertical bearing fixed to the sewing machine, the other of said rolls being mounted on the lower end of a second shaft journalled in a bearing pivotally mounted for swinging movement on a horizontal axis above the rolls and generally in the pass plane of the rolls, means biasing said pivoted bearing to swing toward said fixed bearing, means connected to said first shaft for continuously driving said one roll at a speed greater than the speed at which the bag tops are fed through the sewing machine by said bag [top feeding means, and gears on said shafts at the upper ends of the bearings for driving the second shaft from the first shaft, said gears being meshed throughout a range of swinging movement of said pivoted bearing for maintaining the drive for said other roll despite variations in bag top thickness.

6. In apparatus as set forth in claim 5, said pivoted bearing being swingable away from said fixed bearing to a position for separation of said rolls and gears, and means for retaining said pivoted bearing in said position.

7. In apparatus as set forth in claim 5, said driving means comprising a right-angle worm gear drive at the upper end of the first shaft having its output shaft coupled to the upper end of the first shaft, and having a flexible drive shaft connected to its input shaft.

8. In apparatus as set forth in claim 5, each of said rolls being a resilient roll having helical grooves in its periphery whereby said rolls :are adapted to exert a lift on a bag top gripped therebetween.

References Cited in the file of this patent UNITED STATES PATENTS 1,995,092 Christensen Mar. 19, 1935 2,043,748 Hacklander June 9, 1936 2,156,536 Lutz M May 2, 1939 2,199,005 Marsh Apr. 30', 1940 2,630,086 Kindseath et a1 Mar. 3, 1953 2,688,176 Birch Sept. 7, 1954 2,692,568 Galkin Oct. 26, 1954 2,718,201 Kindseath et a1 Sept. 20, 1955 2,847,955 Peterson Aug. 19, 1958 

1. IN AN APPARATUS FOR CLOSING OPEN-MOUTHED FILLED BAGS, SAID APPARATUS COMPRISING A CONVEYOR ADAPTED TO CONVEY FILLED BAGS IN UPRIGHT POSITION ONE AFTER ANOTHER THROUGH A SEWING STATION, A SEWING MACHINE MOUNTED IN FIXED POSITION AT SAID STATION FOR HORIZONTAL OPERATION OF ITS NEEDLE TO STITCH THE TOPS OF THE BAGS, SAID SEWING MACHINE HAVING MEANS FOR FEEDING THE TOPS OF THE BAGS THERETHROUGH, A SEWING THREAD CUTTER FOR CUTTING THE CHAIN OF THREAD TRAILING A SEWN BAG AFTER THE TRAILING END OF THE BAG TOP EXITS FROM THE SEWING MACHINE, SAID CUTTER BEING OFFSET FROM THE LINE OF STITCHING, AND MEANS FOR MOVING THE CHAIN INTO POSITION FOR BEING CUT BY THE CUTTER; MEANS FOR SUPPORTING THE TOP OF EACH BAG AS IT EXITS FROM THE SEWING MACHINE AND FOR HOLDING TAUT THE CHAIN OF THREAD BETWEEN THE SEWING MACHINE AND THE TRAILING END OF THE BAG TOP TO MAINTAIN SAID CHAIN IN POSITION FOR ENGAGEMENT BY SAID MEANS FOR MOVING THE CHAIN INTO POSITION FOR BEING CUT BY THE CUTTER, SAID BAG TOP SUPPORTING MEANS COMPRISING A PAIR OF ROLLS MOUNTED ON THE EXIT SIDE OF THE SEWING MACHINE IN POSITION FOR GRIPPING THE TOPS OF BAGS EXITING FROM THE SEWING MACHINE IN THE STITCHED ZONE OF THE BAGS, SAID ROLLS BEING ROTATABLE ON GENERALLY VERTICAL AXES AND BEING RELATIVELY MOVABLE TOWARD AND AWAY FROM ONE ANOTHER, MEANS BIASING SAID ROLLS TOWARD ONE ANOTHER FOR GRIPPING BAG TOPS, AND MEANS FOR CONTINUOUSLY DRIVING SAID ROLLS AT A SPEED GREATER THAN THE SPEED AT WHICH THE BAG TOPS ARE FED THROUGH THE SEWING MACHINE BY SAID BAG TOP FEEDING MEANS. 